Threaded container closure



R. FINGOLD 2,313,816

THREADED CONTAINER CLOSURE March 16, 1943.

Filed Dec. 31, 1941 INVENTOR.

ATTORNEYS.

Patented Mar. 16, 1943 UNITED STATES PATENT OFFICE 2,313,816 TIlREADED CONTAINER. CLOSURE Reuben Fingold, Pittsburgh, Pa. Application December 31, 1941, Serial No. 425,067 8 Claims. (01. 215-43) This invention relates to new and useful improvements in container closures such, for example, as lids for ordinary Mason jars and the like.

Heretofore it has been proposed to form the lids or covers for Mason jars and the like from glass with the inner surface of their side walls completely lined with metal threads. Compared to metal lids such a construction is desirable since it both lessens the possibility of contamination of the jar contents by metal and, in addition, reduces the amount of metal used in an article of manufacture which serves household purposes only. However, a common objection to such lids is that the metal threads slip inside of them when the lids are forcefully screwed onto Jars. Such slippage results in imperfect sealing of the Jar and either may prevent the lid from being unscrewed later or may render the lid useless.

Another objection to such lids is that a substantial portion of the metal lining serves no useful purpose in securing the lid to the Jar and is therefore a needless waste of metal. I

It is therefore among the objects of this invention to reduce to a minimum the metal used in such lids and other types of screw closures, and to provide a secure connection between the metal threads and the rest of the lid.

Other objects will appear from the following description of the invention.

In general the objects of this invention are achieved by providing a container closure, typifled by a jar lid, having non-metallic top and side walls with a metal thread that is molded into the side walls and preferably has projections extending into the side wall of the lid to further insure against slippage. The only metal in the lid is the helical thread which, according to an important feature of the invention, is substantially no longer than the thread with which it registers on the jar or other container with which it is associated.

The invention is illustrated in the accompanying drawing in which Fig. 1 is a plan view of a jar lid with portions of the transparent glass broken away to expose certain features of the metal thread; Fig. 2 is a side view, partly broken away, of the lid screwed tightly on a jar; Fig. 3 is a side view of the Jar neck shown in Fig. 2; Fig. 4 is a vertical section of the lid along the line IV-IV of Fig. 1; Figs. 5 and 6 are enlarged fragmentary side views of modified embodiments of the metal threads for the lids: and Fig. 7 a

fragmentary view similar to Fig. 4 showing two alternative details of construction.

Referring in detail to the drawing, a lid designated as a whole by numeral I has a top 2 and a side wall 3. Preferably the lid is molded from glass, although other non-metallic material, such as plastics, may be used. This lid is intended primarily as a cover for a glass jar 4 of the Mason jar type that has a neck 5 encircled by a glass thread 6 molded thereon. To permit the lid to be screwed safely and securely onto the jar, side wall 3 is provided with a metal thread 1 adapted to register with glass thread 6 of the jar. The metal thread is firmly embedded in the glass lid by molding it in the inner surface of side wall 3 at the time the lid is formed.

Another feature of this invention is that the amount of metal used is reduced by limiting the length of the metal thread I of the lid to substantially the length of thread 6 of the jar neck, and a secure connection is obtained by so positioning the metal thread that when the lid has been tightly screwed onto the jar, the metal thread engages the glass thread of the jar from end to end. Waste of metal isthus prevented since the metal is limited to the portion of the lid which is functional in holding the lid to the Jar. All of the rest of the inner surface of side wall 3 is exposed, and in the embodiment illustrated a thread-like channel I0 is formed in the glass wall of the lid continuous with the lower end of thread 'I to accommodate the glass thread of the jar neck during the initial phase of the screwing-on operation. Once the lid has been tightened onto the jar the channel l0 becomes non-functional so it does not need to closely conform to the glass thread. Of course, channel In may be omitted provided the inner lower portion of wall 3 is recessed, as indicated at (Fig. 7 to allow the glass thread 8 on the jar neck to initially engage the metal thread 1 during the assembling of the lid and jar. Such an arrangement is ordinarily less desirable, however, as it may weaken the connection between side wall 3 and thread 1, and perhaps also impair the sealing ability of the lid.

Referring to Figs. 1 and 4, metal thread 1 is anchored in the lid more securely when molded therein by providing it with outwardly projecting detents. In the form shown in Figs. 1 and 4, radial fiarl'ges I are provided which preferably are notched at points 9 so as to form detents. When the lid is molded the glass sets around these detents and embeds thread effectively resists any tendency toward them so that the metal rotational slipping in the lid. Such a flanged thread can be made conveniently by pressing or otherwise forming a channel in a strip of metal, before or after hanging the edges of the strip, and subsequently winding the strip into final helical or thread form.

Modified forms of detents may, of course. be used, two such forms being shown in Figs. 5 and 6. In Fig. 5 the thread has tongue-like detents or projections ll punched outwardly through its side wall. In Fig. 6 the detent I2 is a button-like projection pressed from the metal body. Since the modified threads of Figs. 5 and 6 are not flanged they may be quite simply manufactured by pressing the thread into a metal cylinder and punching or pressing out the projections II or l2. Obviously, flanges 8 may be combined 'with the use of detents such as are shown in Figs. 5 and 6.

It will be understood that various modifications are permissible without departing from the gist of the invention. Thus, it is not restricted to closures for use with Mason type jars but rather is applicable broadly to any type of screw closure where the closure may be fashioned from glass, plastics and similar moldable materials. Also, it is equally applicable to closures which cooperate with threads formed interiorly ot the container neck.

A modification which may be particularly desirable arises from the fact that articles such as glass jars cannot ordinarily be made to close tolerances. Hence it may be that with some types of containers a lid such as shown in Figs. 1 to 4 cannot be screwed far enough onto the Jar neck to eflect an adequate seal, as with a rubber ring, because the thread ends with the upper end of thread I. To overcome this the thread 1 may be extended by molding in the glass at the upper end of lid l a thread 10 (Fig. 7) continuous: with thread I. In this manner variations in the length of the jar neck, or rather in the distance between the lower end of thread i and sealing flange I5, may be compensated for by permitting the lid to be screwed farther down than is possible with the lid shown in Figs. 1 to 4.

According to the provisions of the patent statutes, I have explained the principle and construction of my invention and have illustrated and understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. A closure for a container having a threaded neck, said closure comprising molded non-metallic top and side walls, and a metal thread moldably embedded in the inner surface of said side wall and complementing and substantially limited in length to the length of the thread on the container neck, said inner surface being provided with a thread-like channel forming a continuation of said metal thread.

2. A closure according to claim 1, said continuation extending upwardly from the upper end of said metal thread.

3. A closure according to claim 1, said continuation extending downwardly to the bottom of the closure from the lower end of said metal thread.

4. A closure according to claim 1, said continuation extending upwardly from the upper end of said metal thread and downwardly to the bottom of the closure from the lower end of said metal thread.

5. A closure for a container having a threaded neck, said closure comprising molded non-metallic top and side walls, a metal thread complementing and substantially limited in length to the length of the thread on the container neck, said metal thread being molded into the inner surface of said side wall, and detents formed in the metal thread and projecting outwardly into said side wall.

6. A closure according to claim 5, said detents being tongue-like projections formed on the metal thread and extending radially outwardly into said side wall.

7. A closure for a container having a threaded neck, said closure comprising molded non-metallic top and side walls, a metal thread'complementing and substantially limited in length to the length of the thread on the container neck, said metal threads being molded into the inner surface of said side wall, and flanges formed on themetal thread and projecting outwardly into said side wall.

8. A closure according to claim '7, said flanges being notched to thereby increase the 'detent described what I now consider to represent its action thereof.

best embodiment. However, I desire to have it REUBEN FINGOLD. 

